What is an entity relationship diagram (erd) an entity relationship diagram ( erd) shows the relationships of entity sets stored in a database an entity in this context is a component of data in other words, er diagrams illustrate the logical structure of databases at first glance an entity relationship diagram looks very.
Above is a computer generated entity relationship diagram (erd), which reflects the models, their data and relationships in a ruby on rails project to build an instagram clone the arrows demonstrate.
Learn how to create an entity relationship diagram in this tutorial we provide a basic overview of erds and then gives step-by-step training on how to make.
Conceptual modeling using the entity-relationship model contents • basic concepts: entities and entity types, attributes and keys, relationships and relationship types • entity-relationship schema (aka er diagram) • constraints on relationship types • design choices • enhanced entity-relationship model features. Entity relationship schema compression technique based on use of tables used with constructs of eer (extended entity relationship) model fig 2a, 2b, and 2c exhibit equivalent representation of generalization, specialization, and aggregation using petrol pumps, milestones, garages, hospitals, fire brigades.